Not now? Yes, now.

Quick PSA, by way of one of my friends who actually knows something* about this:

When companies publish software updates and security patches, hackers (not the good kind) can run a diff on the old software versus the new (patched) software and see just what hole the company was patching. They can then take advantage of that knowledge and attack computers that haven’t been updated yet; aka, the systems where someone has pressed “Not Now” instead of “Continue.”